Cotton fiber is held in a cotton boll, and each fiber is attached to one of several cotton seeds in the boll. When the boll matures, the boll opens to expose the fiber. The seeds are retained in cavities created by the open bolls or hulls.
Various types of cotton harvesting devices include mechanisms that contact and extract the cotton seed and fiber from the cotton plant. Harvesting efficiency depends on the ability of the mechanisms to remove the seed and fiber from the open bolls which, in turn, depends on the seed and fiber connection to the cotton boll hulls. If the fiber and seed are strongly linked to the hull, harvesting efficiency can be greatly reduced. Fiber orientation also affects the separating efficiency, and if the fibers are not exposed satisfactorily, the ability of the harvesting mechanisms to contact and remove the fiber is reduced.